A probe system generally includes a mobile probe head and a stationary transceiver element. The probe head in the form of a momentary-contact switch having a deflectable feeler, which outputs a switching signal in response to a deflection out of its rest position or upon a contact of the feeler, is used, in particular, for determining the position of workpieces that are clamped in machines, e.g., machine tools, that process material. In this context, the rest position of the feeler is understood to be a position in which the feeler has no contact with the workpiece to be probe-contacted. Upon contact of the feeler with the workpiece, the feeler is deflected out of its rest position, and an electrical sensor signal is generated by a suitable transducer if the deflection exceeds a specified probe threshold. The electrical sensor signal is frequently converted into an infrared signal, so that a contactless and wireless signal transmission to the transceiver element of the probe system is thus achieved.
The infrared signals are converted again into electrical signals in this transceiver element. The transceiver element of the probe system is connected to an evaluation unit, to which the electrical signals are relayed and evaluated and ultimately made available, for example, to the control of the machine tool. The position of the workpiece to be measured can be determined based on the measured position of the machine tool part in question.
German Published Patent Application No. 103 03 551 describes a probe system of the type indicated above, in which a start signal is transmitted by a transmit element to a probe head, which triggers the preparedness of the probe head for the measuring operation. The probe head, usually operated with a battery, requires a comparatively great amount of electrical energy in this state. For instance, in this active state, the probe head is repeatedly driven close up to various contours of a workpiece, so that in response to any contact with the workpiece, the feeler triggers corresponding switching signals. After the measuring process is concluded, the probe head must be deactivated again by transmitting a control command, and returned to a stand-by state economizing on energy.
In certain conventional probe systems, after a predefined time span, the probe head is returned to the stand-by state by a time-out function.
Thus, certain conventional probe systems have the disadvantage that the probe heads are frequently in the active state of the measuring operation for an unnecessarily long time, and therefore needlessly consume a great amount of electrical energy.